Needled textile laminates and method for producing same



April 9, 1968 N. s. NEWMAN v 3,377,231

NEEDLED TEXTILE LAMINATES AND METHOD FOR PRODUCING SAME Filed June 1l. 1964 I7 I8 l5 United States Patent Gfiice 3,3??,23l Patented Apr. 9, 1968 3,377,231 NEEDLED TEX'HLE LAMINATES AND METHD FSR PRODUCNG SAME Nicholas S. Newman, Cambridge, Mass., assignorto Tire Kendall Company, Boston, Mass., a corporation of Massachusetts Filed June 11, 1964, Ser. No. 374,338 9 Claims. (Cl. 1621-80) ABSTRACT F THE DISCLOSURE A relatively open-meshed fabric is prepared, in which at least some of the yarns are wrapped with a continuous filamentary wrapping strand in the form of loops extending radially outward from the core of the wrapped yarns. A layer of textile-length fibers is needled into the fabric, as in a conventional needle-loom operation. The fibers in the fibrous layer become mechanically entangled and enmeshed with the filamentary loops of the wrapped yarns, whereby the union between fibers and fabric is enhanced.

This invention relates to conformable composite textile products. More particularly, it relates to textile products, suitable for use as linings, blankets, and the like, wherein a stretch fabric of a certain construction is united, as by needling, to a layer of unspun, unwoven textile fibers.

It is known to employ a needle-punching or tufting or similar mechanical operation to secure a fibrous batt of unspun and unwoven textile fibers to a woven or knitted fabric. Such composite textile products, herein referred to as laminates, may also contain a layer of rubber or polyurethane foam as an element of construction, and their use has been proposed for blankets, insulating liners, and the like. Such prior art products, however, are generally deficient in the degree to which the fibrous layer is anchored to the fabric. Considering that the fibers which constitute the yarns of the fabric and the fibers which constitute the fibrous batt are generally disposed in parallel but independent horizontal planes, the only anchorage between fibrous batt and fabric occurs where the needling operation has regrouped some of the fibers into bundles so that some of said fibers are reoriented from their normal horizontal position to a vertical position, with fibrous bundles plunging through the depth of the fibrous batt and engaging with the interstices of the fabric.

For end uses where the composite laminate remains static, such a modest degree of union between fibrous batt and fabric may be sufficient. In many applications, however, the composite laminate undergoes repeated expansion and contraction, which tends to loosen the fibrous bond between the fabric and the fibrous batt. Pilling of the textile fibers in the batt is observed, and the wet or dry abrasion resistance of conventional composite laminates of this type is of a low order. Attempts to improve the union between a fibrous batt and a textile fabric have been made by the use of adhesives. However, this is not only an expensive operation, but an adhesive layer between fibrous batt and textile fabric restricts the ready stretch and conformability desirable in such acomposite laminate. Repeated needling of the fibrous batt into the fabric has also been resorted to. This in turn gradually renders the fibrous batt more dense and less pliant, decreasing both the desired insulating value and the conformability. Moreover, repeated needling reduces the ready stretch of the composite laminate, ready stretch denoting the percentage of elongation shown when a five pound weight is hung on one end of a strip of laminate one inch wide.

I have found that composite laminates of this type can be made with enhanced loft, insulating value, ready stretch, and fiber-to-fabric anchorage if at least some of the yarns in the fabric are made according to the disclosure of U.S. Patent No` 3,078,653, of common assignee with the present application. In U.S. application Ser. No. 212,922, of July 27, 1962, now U.S. Patent No. 3,154,111, also of common assignee, there is described the use of the yarns of Patent No. 3,078,653 in the preparation of fabrics. It is with composite laminates between fibrous batts and fabrics of this particular type that the present invention is concerned.

It is a ,primary object of this invention to provide a conformable and elastic composite textile laminate comprising a layer of textile-length fibers mechanically united to a fabric which consists at least in part of wrapped yarns in which the wrapping strand is disposed into filamentary loops extending radially from the axis of the yarn.

It is a more specific object of the invention to prepare such a laminate in which a substantial portion of the textile-length fibers are mechanically embedded beween the flamentary loops of the wrapping strand while still remaining horizontally disposed.

Other objects of the invention will be apparent from the following description and the drawings, in which:

FIGURE 1 represents a perspective View of one produce of this invention.

FIGURE 2 represents a section of the product of FIG- URE l taken along a pair of yarns, to shown the characteristic union obtained by needling.

FIGURE 3 represents a cross-section taken along a single yarn to shown the fiber-filament entanglement which enhances the fiber-to-fabric union.

FIGURE 4 is a cross-section taken across the axis of a similar yarn of the laminates of this invention.

Referring to FIGURE l, a composite textile laminate 10 is formed by superimposing a layer of unspun and unwoven fibers 12 on a fabric 14, the nature of which is set forth more fully below. The layer of fibers may be the customary fleece or batt delivered from one or more cards, garnetts, or air-lay machines, and may be either iso-'tropically oriented or arranged in more or less parallel fashion. In either case, the fibers are disposed substantially in a horizontal direction. Any fibers of sufficient length to allow processing on textile equipment may be used, including natural fibers such as cotton or wool, other cellulosic fibers such as various rayons and acetates, and synthetic fibers such as those derived from polyamides, polyesters, polyolefines, and plain or modified polyacrylics and the like.

The fabric layer 14 is, as set forth above, described generally in U.S. kPatent 3,154,111. It comprises yarns arranged in over-and-under intercrossing relationships to form a textile fabric. In `the case of a Woven fabric, at least the filling yarns, or a substantial proportion thereof, are wrapped yarns represented in cross-section by FIGURE 4, wherein a continuous filament wrapping strand 24 is wrapped around a core strand 20 in the form of bifilar turns and doubled-back lamentary loops which extend in a somewhat irregular manner outwardly and vradially from the Iaxis of the core strand. This core stran-d 20 may be one `or more strands of elastic filamentary'material such as rubberor spandex, or it may be a so-called stretch yarn, this term relating to multifilament yarns composed of synthetic polymeric material capable of being treated to develop a stretch or elastic character. Different types of elastic yarn have different moduli of extension and different degrees of potential elongation, and the choice of yarn will depend on the desired nature of the final product.

In general the fabric 14 is woven as a relatively openmeshed product knownas a scrirn, varying from about a 14x8 or20x10uptoacountof28x24or32x28. Due to the intimate contact between the wrapping strand and the core strand, if yarns with a stretch rather than an elastomeric core strand are employed in this invention, the yarns will be inelastic as they enter and leave the loom. The scrim fabric, therefore, at the point of being united to the fibrous layer is stable and inelastic in this case.

The union between fibrous layer and fabric may be effected by needling in a needle loom, punching, tufting, or otherwise diverting at least some of the fibers in the fibrous layer out cf their horizontal plane lto plunge vertically downward through the fibrous layer and through the interstices of the scrim. Such a situation is shown in FIGURE 2, wherein some of the fibers 16 of a horizontally-disposed fibrous layer have been reoriented vertically through the interstitial space between a pair of warp yarns and a pair of filling yarns 17, to unite with the fabric mechanically as shown at 18. The wrapping strand which would be associated with either or both of the warp and filling yarns has in FIGURE 2 been omitted in order to show more clearly the effect of needling.

It is characteristic of the process of this invention that due to the peculiar relationship developed between the fibers of the fibrous iayer and the radial loop wrappings of the Wrapped yarn, only alight needling, such as one or two passes through a needle loom at 200 strokes per square inch, is sufficient to provide a degree of union between the fibrous layer and the special scrim which is superior to that provided by three or four needlings of the same fibrous layer through a scrirn of similar construction but employing conventional yarns. This superior union is particularly noticed when the products of this invention are washed or are subject to wet abrasion, inasmuch as they show a high resistance to delamination, piiling, and fiber shedding. This ability to promote a strong union with only a light needling, as mentioned above, allows the preservation of an enhanced loft, softness, conformability, and insulating value in the final product. l'

After the hitherto inelastic scrim and the fibrous layer have been thus united, the composite laminate is then treated, cutornarily by moist steam, to allow the stretch yarns of the fabric to relax and develop elasticity. Open steaming, in a continuous process or steam tumbling may be used, the process being carried out until the required balance of shrinkage and development of elasticity has been obtained. If the stretch core strand in the wrapped yarns is of a set-table nature, the laminate may be stabilized against further shrinkage or contractlon by, for example, heating it to a setting temperature while holding the laminate at the desired dimensions.y

The nature of the engagement between the fibers of the fibrous layer and the wrapping strands of the yarns of the fabric layer is shown more clearly in FIGURES 3 and 4, which are sections taken along and across the axis of one typical yarn in a laminate of this invention. In each case, a stretch core strand is wrapped in bifilar or loop conformation with a continuous filament wrapping strand which is disposed in a series of unbroken, radially-extending filamentary loops 24. In general it will be found that the spacing between these wrapping filamentary loops is greater than the diameter of the fibers in the fibrous layer. The mechanical working of the needling operation, and -rnore particularly the fulling action of the steaming and finishing operations, encourage the embedment of the textile fibers 26 down into the yarn structure, so that the fibers .penetrate between the loops of the wrapping strand and are held thereby. In FIG- URE 3, the yarn may be considered to be running in the filling direction and the fibers to be substantially oriented in the machine direction, which would correspond to the warp of the fabric. The fibers 26 therefore appear in cross-section. FIGURE 4, a section taken across the yarn, shows the fibers 26 embedding in the loops 24 in a CII 4 view that is 90 displaced from the view of FIGURE 3.

As mentioned above, the laminates of this invention are conformable, and find utility in the stretch lining field. Such utility is of growing importance in view of the popularity of stretch apparel fabrics and stretch outerwear garments in general. Many such garments must be lined, to promote their insulating value. The functional value of such garments, residing in their elasticity and recovery, is severely impaired if the lining of the garment cannot match the stretch and recovery of the outer fabric. By the process of this invention, composite textile laminates suitable for garment lining use can be prepared with a ready stretch of 20% to 80% or more, as defined above. By suitable choice of the stretch core strand, the degree of elongation possible in the final laminate can be pre-set to match the elongation parameters of the other fabric layers in the garment.

Although the above description related to the uniting of one layer of textile fibers with a fabric, it is, of course, possible to unite layers of textile fibers to both faces of such fabrics, to develop blanket-like structures that are of high insulating value and are conformable. Such stretch blankets are of particular utility as crib blankets, where a stretch of 20% or 30% allows the retention of a snug fit despite the body movements of an infant. The composite laminates of this invention can be napped or brushed, before or after shrinkage, if greater thickness and surface softness are desired.

The following examples will illustrate methods of carrying out the process of this invention.

Example l A base fabric of 20 x 10 construction was made using 3ls cotton yarns in the warp. The filling yarns were wrapped yarns of the type described in U.S. Patent 3,078,653, and consisted of a 70 denier spandex core with a 70 denier 34 filament nylon scaffolding core strand, both wrapped with a denier 20 filament acetate strand. The wrapping was such as to render the composite yarn inelastic. The final yarn denier was about 700, and the yarn analysis was 87.8% acetate, 10.1% nylon, 2.1% spandex. Wrapping was effected at 400% extension of the spandex core strand.

Using an air-lay machine, a batt of acrylic fibers was prepared, weighing 70 grams per square yard, the `fibers being 3 denier and 19/16 inches long.

The fibrous layer and the fabric were combined and needled twice in a Hunter needle loom, at a rate of 200 strokes per square inch in each pass or 400 strokes total.

The composite laminate was then steam-tumbled for 30 minutes an-d then tumble-dried. The hitherto inelastic laminate showed a shrinkage of 18% in the warp direction and 60% in the cross direction. It had a ready stretch of and after 10 repeated stretchings it still recovered 86% of its original dimension. Its suitability as a lining material was shown by good resistance to fiber loss and to delamination on machine washing, and by negligible shrinkage.

Example 2 The procedure of Example 1 was repeated except that two 70 gram Orlon batts were used, one being needled to each face of the base fabric to form a blanket structure.

The blanket shrank 10% in the warp direction and 54% in the cross direction during steam tumbling. The finished product has a ready stretch of 80%, a recovery of 86% after 10 stretchings, and good resistance to machine washing coupled with negligible shrinkage.

Example 3 The same base scrim fabric was combined as in Example 1 with a batt of Acrilan fibers (an acrylic fiber from The Chemstrand Corporation), the fibers being a mixture of 50% 3-dcnier, 40% S-denier, and 10% 8- denier.

5 The laminate shrank l7% in the Warp and 55% in the cross directions during steam tumbling. The finished product had a ready stretch of 80% and a recovery of 83% after l stretchings. It also had good resistance to machine laundering and negligible shrinkage.

Example 4 The procedure of Example 3 was repeated except that two 120 gram Acrilan batts were used, one being needled to each face of the base fabric to form a blanket structure.

In steam tumbling the blanket shrank 8% in the warp direction and 50% in the cross direction. The nished blanket had a ready stretch of 55% and a recovery of 90% after 10 repeated stretchings. It showed negligible shrinkage and good durability on machine laundering.

Example 5 Using the same procedure as in Examples 1 and 3, a 200 gram per square yard polypropylene fibrous batt was needled twice to the same ibase scrim.

In steam tumbling the laminate shrank 3% in the warp direction and 35% in the cross direction. The final prod- Iuct had a ready stretch of 60%, with 83% recovery after stretchings. It showed negligible shrinkage and good durability on machine laundering.

Example 6 The procedure of Example 2 was repeated except that in place of steam tumbling, the blanket was gently steamed in a continuous process until a cross-direction shrinkage of 35% was reached. In this condition the fabric was pinned to a frame to maintain dimensions and was heat-set at 325 F. for 3 minutes. The final blanket had a ready stretch of 35 and showed no shrinkage in subsequent machine washing.

This latter procedure is a convenient device for setting the shrinkage and extensibility of composite textile laminates of this sort, taking advantage of the heat-settable nature of spandex cord strands.

Although the above examples are concerned with laminates which stretch in the filling direction, it is equally possible to produce warp-stretch laminates, as the following example illustrates.

Example 7 A warp-stretch fabric was produced using the elastic yarn of Example 1, 10 ends per inch, in the warp. The filling was 22 picks per inch of 40s cotton yarn wrapped With 55 denier 15 filament dull acetate according to U.S. Patent No. 3,076,307. To this was needled a 70 gram per square yard batt of Acrilan fibers, using three passes through the needle loom at 1A inch penetration. The laminate was then shrunk by steam tumbling and tumble drying, during which it shrank 50% -in the warp direction and 10% in the filling.

The final .product had l150% ready stretch in the warp direction, with 94% recovery after =10 elongations, and had excellent resistance to delamination.

Having thus described my invention, I claim:

1. A conformable and elastic textile laminate comprising:

at least one layer of relatively open-meshed fabric comprising yarns disposed in over-and-under intercrossing relationship,

some a-t least of said yarns comprising a stretch core strand and a continuous filament wrapping strand disposed about said core strand in the Aforni of double-back loops and bifilar turns,

said loops extending generally radially outward from the core strand axis,

and at least one layer of textile-length fibers in uns pun and unwoven form,

some at least of said 'bers being grouped into fibrous bundles oriented normal to the horizontal `or main plane of the laminate and extending downwardly and vertically through the interstices of the fabric and being mechanically engaged with said interstices,

and a substantial portion `of the textile fibers which remain in a horizontal plane being enmeshed and entangled with the radially-extending loops of Wrapping strand disposed about the core strands of said open-meshed fabrics.

2. A product according to claim 1 wherein the stretch core strand is `of the spandex type.

3. A produc-t according to claim 1 wherein the stretch core strand is a multilament strand of synthetic polymeric material `capable of retracting when heated.

'4. A product according to claim 1 in which the base fabric is a scrim of a count between 14 x 8 and 32 x 28 and in which the wrapped yarns are in the filling `direction.

5. A product according to claim r1 in which the laminate has a ready stretch of between 20% and 80%.

6. A method for preparing a conformable and elastic textile laminate which comprises:

forming a fabric of yarns dispose-d in over-and-under intercrossing relationship,

some at least of said yarns being elastic yarns comprising a stretch core strand and a continuous filament wrapping strand disposed about said core strand in the lform of doubled-'back loops and bifilar turns,

said loops `extending generally radially outward from the core strand axis,

superimposing on at least one face of said fabric a layer of unspun and unwoven, horizontally-disposed textile-length fibers,

displacing some of said bers 1Into a ver-tical position extending downwardly through said layer of fibers Iand through some of the interstices of said fabric to engage mechanically with said interstices, and shrinking the composite laminate.

7. A method according to claim 6 wherein the elastic yarns are in the filling direc-tion of the fabric and the shrinkage is effected by heat.

8. A method according to claim 6 wherein the elastic core strand is of the spandex type, and in which the laminate, after shrinkage, is stabilized against further shrinkage by heating the laminate to a temperature of at least 300 F.

y9'. A method according to claim 6 'wherein the elastic yarns are in the Warp direction 0f the fabric and the shrinkage is effected by heat.

References Cited UNITED STATES PATENTS 2/1951 lFrancis 161-85 2/ 1961 Morgenstern 1'61-81 

